Hitachi, Ltd.

Yuichi Mori

Shunsuke Akifuji

Tetsuji Toge

Hiroshi Majima

Kazuhiro Suga

Kazuyasu Tsuiki

Kenichi Aoshima

Kansuke Kuroyanagi

Tomohide Sugimoto

Etsuko Iwama

Ryogo Honda

Takeshi Atago

Masami Nagano

Keiichi Mashino

Katsuji Marumoto

Atsushi Kanke

Masahide Sakamoto

In an Internet telephone connection method, a communication bandwidth is managed by using a bandwidth controller, gateway devices and voice relay routers to monitor communication quality under bandwidth reservation. A communication path under bandwidth reservation is preferentially selected by using gate keepers and the voice relay routers, and the connection of the Internet telephone is performed. A problematic device is prohibited from being selected as a connection-destination device at the time of a call setup and the problem restoration is monitored by using the gate keepers and the gateway devices. Further, a device having invalid attribute information is prohibited from being selected as a connection-destination device at the time of call-setup, and the restoration of the attribute information is notified to the overall network. Accordingly, the reservation of the communication bandwidth can be performed under the control of the overall network, fixed communication quality can be maintained and reliability can be enhanced.

Internet telephone connection method, bandwidth controller and gate keeper

A digitized document circulating system includes a unit provided in a transmission source of a digitized document and for sending the digitized document, a unit for delivering the digitized document to a transmission destination to thereby circulate the digitized document, a unit provided in the transmission destination and for receiving the digitized document, a unit operated by the delivery unit and for obtaining a circulation history containing delivery time, an identifier of the digitized document, the transmission source and the transmission destination, a unit for reading the circulation history and transferring the circulation history to a requester in response to a request for the circulation history issued from the requester, and a unit for displaying the circulation history received.

Digitized document circulating system with circulation history

A charging generator for a vehicle including a field winding rotated by the rotation of an engine so as to generate a rotating magnetic field; an armature winding responsive to the rotating magnetic field to generate a current and charge a battery via a rectifier; a comparison circuit for comparing a voltage of the battery or a voltage of the rectifier with a predetermined value; a current control circuit for controlling a field current to be supplied to the field winding on the basis of output of the comparison circuit; a voltage change value detection circuit for detecting a change value in the battery voltage or the rectifier voltage; and a load response control circuit for suppressing a rise in the field current to be supplied to the field winding on the basis of an output of the voltage change value detection circuit.

Charging generator for a vehicle including a circuit for suppressing a

A control system for controlling the full current of a generator for a vehicle having an internal combustion engine operates to control the field current so as to change the output power of the generator. A storage unit is charged by the generator; a field current control unit for controlling the field current of the generator detects the output generated by the storage unit; and an engine control unit to which operation parameters of the internal combustion engine are applied controls at least one of a fuel supply and an ignition timing for the internal combustion engine. The engine control unit further operates to determine a kind of change of load being applied to the internal combustion engine when the load has changed and to control the field current of the generator in accordance with a predetermined control pattern corresponding to the kind of change of the load.

Control system for generator mounted on vehicle

Growing community of inventors

Fujisawa, Japan

Yuichi Mori